This invention relates to fireplace gas burners, and more particularly to a gas burner assembly with associated artificial logs for providing a burning flame pattern similar to that produced by burning natural wood logs in the fireplace.
In gas fireplaces a gas burner can be provided for igniting the logs; and usually, permanent and reusable artificial logs are used so that it is not necessary to replenish the logs. A common drawback of such gas fireplace burner and artificial logs asembly is the lack of likeness of the flaming pattern to that of a natural wood log fire. An important and most desirable pattern of the natural wood log fire is the appearance of yellow flames flickering among the logs. Heretofore, assemblies of gas burner with artificial logs suffered the drawback of unable to produce such flickering yellow flames without the inherent formation of unacceptable level of harmful carbon monoxide gas. The production of carbon monoxide gas is, in many instances, further increased when the primary air shutter of such gas burners is erroneously set by the user.
Moreover, the artificial logs commonly are made of a refractory material such as concrete. Such concrete logs require considerable time to heat up, thus increasing impingement of the flames. Since the national standards of gas burners require that a sample of the ignited gas from the burner to be taken within three minutes from the start up, it has been generally experienced that only very hot (about 3500.degree. F.) blue flames will meet such requirement for acceptable level of carbon monoxide gas in gas ignition.